The ability of microtubules to undergo rapid and slower is associated with the ability of the to explore the cell and locate chromosomes.

The ability of microtubules to undergo rapid depolymerization and slower polymerization is associated with the ability of the spindle apparatus to explore the cell and locate chromosomes.

Explanation:

Microtubules are tubulin polymers that make up part of the cytoskeleton and provide eukaryotic cells with framework and shape. These are formed by polymerizing the dimer into protofilaments of two globular proteins, alpha and beta tubulin, which can then be combined laterally to form the microtubule, a hollow tube.

Tubulin dimers can attach two GTP molecules, one of which may be hydrolyzed following assembly. Tubulin dimers are in GTP-bound state throughout polymerization. Once hydrolysis reaches to the peak of the microtubule, a rapid depolymerization and shrinkage is initiated.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.